For Orgelkraft, John Derek Bishop alias Tortusa has created a sound installation of mobile loudspeakers. The speakers are mounted in cardboard tubes, and the music played back is built on samples from the Stavanger concert hall organ.

In addition, John Derek takes part in the project ORGELKRAFTWERK, as the main beat programmer.

John Derek is a Norwegian/American electronic musican and composer, based in Stavanger. When he operates as Tortusa, his identity lies in ambient electronic music. Tortusa's album "I know this place - The Eivind Aarset Collages" is released in March 2016. Samples from Eivind Aarsets catalogue are processed and mixed with modular synthesizers, tape machines, samplers and other devices.